<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <title>文件下载</title>
</head>
<body>
<a href="/downloadServlet?filename=1.jpg">1.jpg</a><br>
<a href="/downloadServlet?filename=2.txt">2.txt</a><br>
<a href="/downloadServlet?filename=3.zip">3.zip</a><br>
</body>
</html>